<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>Document</title>
	<style>
		p {
			font-size: 20px;
			color: green;
		}
	</style>
</head>
<body>
	<div>css选择器</div>
	<p>css选择器</p>
</body>
</html>